@article{melton_zhu_guo_ambrosetti_pederiva_mitas_2016, title={Spin-orbit interactions in electronic structure quantum Monte Carlo methods}, volume={93}, ISSN={["2469-9934"]}, DOI={10.1103/physreva.93.042502}, abstractNote={We develop generalization of the fixed-phase diffusion Monte Carlo method for Hamiltonians which explicitly depend on particle spins such as for spin-orbit interactions. The method is formulated in zero variance manner and is similar to treatment of nonlocal operators in commonly used static- spin calculations. Tests on atomic and molecular systems show that it is very accurate, on par with the fixed-node method. This opens electronic structure quantum Monte Carlo methods to a vast research area of quantum phenomena in which spin-related interactions play an important role.}, number={4}, journal={PHYSICAL REVIEW A}, author={Melton, Cody A. and Zhu, Minyi and Guo, Shi and Ambrosetti, Alberto and Pederiva, Francesco and Mitas, Lubos}, year={2016}, month={Apr} }
 @article{zhu_mitas_2013, title={Study of Ne-core and He-core pseudopotential errors in the MnO molecule: Quantum Monte Carlo benchmark}, volume={572}, ISSN={["0009-2614"]}, DOI={10.1016/j.cplett.2013.04.006}, abstractNote={Abstract Accuracy of effective core potential (ECP) is studied for two sizes of cores by density functional theory, Hartree–Fock and quantum Monte Carlo (QMC) methods using the MnO molecule as a test system. We compare the energy differences between high-spin and low-spin states that were previously found to be problematic for transition metal oxide solids calculations with ECPs. In order to disentangle errors caused by ECPs and by subsequent methods used in calculations, we construct a scalar-relativistic He-core ECP for Mn atom. We find that within high quality correlated calculations both Ne-core and He-core ECPs provide energy differences with comparable, high accuracy.}, journal={CHEMICAL PHYSICS LETTERS}, author={Zhu, Minyi and Mitas, Lubos}, year={2013}, month={May}, pages={136–140} }